Are HIIT Classes Really More Effective Than Steady-State Cardio?

Whether you love cardio or hate it, getting your heart rate up is an excellent way to burn calories. Cardiovascular exercise helps to encourage a healthy weight and a healthy body, reducing your risk of disease, busting stress, and helping you stay in tip-top shape for your daily activities. 

While any activity that gets your heart rate up is considered cardio, two popular forms are steady-state or traditional cardio and high-intensity interval training (HIIT). If your goal is weight loss, you may be wondering which type of cardio is more effective. To find out, we asked Fit Body trainers Nicci Robinson and Brittany Lupton.

How Steady-State Cardio Helps With Weight Loss

Any activity that burns calories can help with weight loss, and traditional cardio does just that. Traditional cardio is any activity that gets your heart rate up, and you maintain it for the whole workout, particularly in the “fat-burning” zone. “That zone is usually in a range between 165–185 BPM,” says Robinson. 

Essentially, traditional cardio helps with weight loss by burning calories. Although you can lose weight by reducing the number of calories you consume, it’s easier and more of an effective strategy to create a calorie deficit with exercise.

“It is important to understand that we lose weight by burning more calories than we take in. Traditional cardio, or "aerobic exercise,” like running, swimming, and dancing, helps with this by increasing your heart rate and overall metabolism, which in turn causes you to burn more calories,” says Lupton. 

Benefits of Steady-State Cardio

Weight loss is only one benefit of traditional cardio. There are many other reasons why performing aerobic activity is a wise choice. Lupton and Robinson provide these reasons:

• Great for heart health
• Builds up endurance for longer workouts
• Activates immune system to help prevent illness
• Reduces health risks: obesity, high blood pressure, type 2 diabetes, heart disease
• Helps to better control blood sugar
• Improves lung function
• Helps decrease anxiety and stress
• Improves sleep
• Increases endorphins (better energy and moods)

How HIIT Helps With Weight Loss

HIIT is another form of cardio that is performed a little differently, as Lupton describes: “With HIIT, you go all out, in short, intense bursts of exercise followed by short periods of rest, then repeat. So instead of running a mile in 10 minutes, you sprint a 100m dash in 20 seconds, rest for a minute, and repeat that 3–6 times.”

Just like traditional cardio, HIIT helps with weight loss by increasing calorie burn. However, there are some different physiological aspects at play when it comes to HIIT. “HIIT is believed to have the 'after-burn effect,’ which is when the body's metabolism is increased for hours after exercising. This can help aid in weight loss because your metabolism is still burning calories after your workout,” explains Lupton.

This after-burn effect is called excess post-exercise oxygen consumption, or EPOC, and is caused by your body’s attempt to get back to normal after working in an anaerobic state. Anaerobic activity is the key to HIIT and is the state you work in during the high-intensity phases of a HIIT session. These intense bursts cause a lot of what’s called oxygen debt, which makes your body work extra hard to keep up with the oxygen and energy you need. Once your workout is over, your body burns more calories trying to recover.

Benefits of HIIT

While HIIT provides you with all of the same benefits as traditional cardio, there are some additional ones, according to Lupton and Robinson:

• Burns more calories in a shorter period (efficient)
• Increases metabolism
• Promotes weight loss without muscle loss
• Can help you lose fat
• Improves oxygen and blood flow
• Builds a healthier heart
• Can be a fun mix of training
• Improve cardiovascular health 

Steady-State Cardio vs. HIIT: Which Is More Effective?

While both are effective, aerobic and anaerobic exercise affect the body and heart differently. Lupton explains: “Cardio is any exercise that leads to a sustained rise in heart rate while the activity is taking place. Traditional cardio (jogging, swimming, biking) is aerobic, meaning our muscles have enough oxygen to perform it for an extended period—this puts less stress on our body and does not burn as many calories.” For these reasons, traditional cardio is excellent for those who prefer more extended exercise periods or who may need lower-impact exercise options for health reasons.

On the other hand, HIIT is anaerobic, meaning the short, intense bursts of exercise require more oxygen than our body can provide. “These short intervals can burn more calories than traditional cardio due to the increased payload we put on our body during the workout and the ‘after-burn effect,’ which is the period after the training when our body is still burning calories,” explains Lupton. HIIT is great if you want to burn more calories in a shorter amount of time. Studies have also shown HIIT to be an excellent way to burn fat while maintaining muscle mass, likely due to its ability to increase growth hormones, which traditional cardio lacks.

The Takeaway

Both traditional and HIIT cardio are very effective in terms of overall cardiovascular health and weight loss. “HIIT can burn more calories in a shorter period due to the high intensity of the workout, but traditional cardio is just as effective if the person is putting in the time, energy, and effort into every workout,” concludes Robinson. In all, the effectiveness is dependent upon the person. If you prefer one style of cardio over another, you can undoubtedly prioritize it and see results. The most significant factor in any training’s effectiveness is consistency, so do what you love and mix it up by trying another cardio form once in a while.